But the plan is contingent on a host of factors _ including cooperation from Mother Nature, which has so far not blessed the Kulluk’s travels in the Gulf of Alaska.

Shell was using its chartered Aiviq anchor-handling vessel to tow the unpropelled rig across stormy seas when that tow line broke and the Aiviq’s four engines malfunctioned on Dec. 27. After a failed five-day fight to tow the Kulluk conical drilling unit to safe harbor amid four-story waves and 70-mph winds, the crew of a powerful tugboat deliberately let its line go, sending the rig along Sitkalidak Island’s shore.

Tide conditions are more favorable now than they will be in coming weeks, adding some urgency to the operation. There also are fears that the longer the Kulluk is stranded at Sitkalidak Island, the greater the chance that it will be further damaged and some 140,000 gallons of diesel fuel could spill.

Coast Guard Capt. Paul Mehler said the main concern is “to do this right” and ensure “that we have all the steps, all the equipment and all the contingencies in place.”

In a news conference Saturday, Mehler stressed that responders were walking through all of the possible scenarios for what could go wrong.

Steven Russell, state on-scene coordinator from the Alaska Department of Environmental Conservation, said there should be no environmental risk from assessing the Kulluk in nearby Kiliuda Bay, but officials are requiring spill response vessels and equipment to be stationed nearby just in case.

Regulators are “confident that the Kulluk recovery operation can be conducted with limited or no environmental impact,” Russell said.

Although the Kulluk remains upright and no sheen has been spotted near the rig, divers have not been sent underwater to survey its hull or the seabed at the site. If a leak occurs during the recovery operation _ or is discovered then _ Russell said the unified command “certainly would reevaluate taking a leaking vessel” into Kiliuda Bay.

Officials have taken fire for not removing more fuel from the Kulluk before the Coast Guard evacuated 18 crew members on Dec. 29. Sean Churchfield, operations manager for shell Alaska, defended the decision and insisted it was safest at this stage to leave the fuel on board.

It is unclear whether the Kulluk can be repaired even if it can be freed intact. Salvage crews on the Kulluk have discovered wave and water damage inside the rig, along with inoperable emergency generators. A number of water-tight doors were breached. One compartment, or void, surrounding the Kulluk’s inner hull also was damaged.

For now, at least, the rig is sound and fit to tow, officials said, citing an assessment by naval architects.

Although Shell owns the Kulluk rig, it is operated by drilling contractor Noble Corp. Salvagers are slated to be on the rig during its 30-mile recovery tow.

Shell officials defended their decision to rely on the Aiviq to try to tow the Kulluk during the recovery operation, given its engine problems just one week ago. Churchfield said the company that owns that vessel, Edison Chouest, has been focused on making sure it is in good shape.

They refused to provide tow or contingency plans to reporters. Federal officials also have been preventing outsiders, including those affiliated with environmental groups, from flying close to the rig. The Federal Aviation Administration is maintaining a temporary flight restriction, and a Coast Guard cutter is patrolling a safety zone one nautical mile around the Kulluk. Officials with the Unified Command of Shell, the Coast Guard, state officials and other partners said the restrictions “were put in place to ensure the safety of response personnel, as well as local mariners and aviation pilots.”

Ships have descended on the area from as far away as Seattle to help out. Some recovery equipment was being flown across the globe. Although most equipment is already on site, responders are still waiting for a military helicopter to deliver a large generator and a tow connection.

Coast Guard, Shell and others operating as a single “unified command,” said they are abiding by a wildlife protection plan and have arranged for bird rescue programs in case they are needed. Protected species observers also will be on the scene.

The incident has provided fresh ammunition to critics of offshore drilling, who say it illustrates how even routine operations far from offshore wells can be risky. The Kulluk finished drilling the first half of an exploratory oil well in the Beaufort Sea for Shell in October.

Jennifer A. Dlouhy covers energy policy, politics and other issues for The Houston Chronicle and other Hearst Newspapers from Washington, D.C. Previously, she reported on legal affairs for Congressional Quarterly. She also has worked at The Beaumont Enterprise, The San Antonio Express-News and other newspapers. Jennifer enjoys cooking, gardening and hiking. She lives in Washington, D.C., with her husband and toddler son.

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